It is known to prove a motor car with frameless windows on the driver and passenger doors in which there is no frame member engaging along a top edge of these windows when the associated door is open. When the door is open, the window can be raised to a position which is slightly below the fully closed position. Then, when the door is shut, the window is raised to a fully closed position in which it seals into a seal extending along the bodywork of the vehicle above the window. Later, when the door handle is operated to open the door, the window is lowered out of the seal to enable the door to be opened without interference between the seal and window during this process. This arrangement can allow fairly good sealing, but the window can only move at a finite speed and there is a delay in time between when the door handle is operated and when the door can actually be opened. Furthermore, in some cases of total vehicle power failure or when emergency vehicle evacuation is desirable it may not always be particularly easy to open the vehicle doors.